The present invention relates to a plant or apparatus utilizing a universal straightening - bending machine.
More specifically, this plant or machine is utilized for straightening and bending of rods or metallic wire and hence for the realization of small or large stirrups, and more particularly, for the bending and shaping of relatively long rods and even to the respective opposed extremities of the rods
In the prior art, it is known that the straigntening of rods can be performed by special machines called straightening machines.
Less preferably, stirrup/bending machines that comprise even straightening means (e.g. AT-B-368725 in the name of EVG, Italian patent application in the name of same inventor IT-83342A/85 and IT-83426A/85 corresponding to EP-86102121.0) are used. These stirrup/bending machines perform other functions than just straightening the rods. For instance, in AT-B-368725, straightening action is performed on the corresponding bending plane whereas in other solutions, the straightening action is performed on different planes, the bending plane in which lies the corresponding cutting and bending group being disposed more or less inclined to the vertical.
These types of machines, that performed the straightening action before the bending action, are inherently difficult for straightening and shaping of rods of notable lengthiness.
Other drawbacks of all this category of machines (known generally as stirrup machines), is that they cannot produce stirrups or shaped rods of great size since it is impossible to rotate lengthy and large diameter bars on a vertical or inclined plane.
Other drawbacks encountered by these machines for the production of small-size stirrups (for example, for reinforced concrete), for the reason of the presence of the bending journals and anvil means, is extremely difficult as the finished stirrups discharged must be collected and transferred to another location within the plant.
Further inconvenience lies in producting spiral stirrups formed by bending an axial bar for the respective support, this limiting the length of the spiral sliding in the bar.
Finally for the production of stirrups or relatively long rods, horizontal benches are used comprising:
a sole bending group wherein an extremity of the bars is first and then bent to scroll causing the bar near one extremity, and then finally bending the other opposed extremity,
or two moveable adjustable bending groups for shaping contemporaneously contemporarily the two opposed extremities of the bar.
These benches are complex and designed for bending operations wherein the rods are shaped solely by manually or mechanical bending. These benches are not conducive to automatic feeding and straightening operations.
U.S. Pat. No. 3,052,277 (STEGMANN) discloses a bending machine with work bending table pivotable about a horizontal axis to move the work table in any desired inclination including angular displacement exceeding 90.degree. relative to the horizontal plane. Although the Stegmann bending machine allows the table to be moved to a preferred working position, it does not provide a sufficient means for discharge of the produced stirrups.